Whitworth wrench/tool set

Joined
Dec 7, 2013
Messages
48
Country flag
Hello all,

I have many wrenches in my garage but none of them seem to fit on any darn bolt on my Commando. My neighbor told me that the British have a differently sized set of tools than we do here in the USA. Is Whitworth the right "style"? As opposed to SI/Metric/JIS.

If so then can anyone here recommend a place where I can purchase a set of Whitworth tools at a reasonable price? I see some Norton Specific tool rolls but the prices make me cringe. $90 for 8 wrenches hurts. :eek:

Thanks for your help!
 

marshg246

VIP MEMBER
Joined
Jul 12, 2015
Messages
1,386
Country flag
The vast majority of the nuts and bolts on a Commando are SAE. The gearbox isn't and some of the engine is not. There's some good info here: https://britishfasteners.com/help.html It can be quite confusing CEI/BSW/BSF/BSC/BA and so on. Fortunately even though most (all?) of those are used, they generally don't require tools for each type. People (especially us Americans) tend to use Whitworth to mean any British standard. There is not much Whitworth in a Commando or British bike in general. I think CEI/BSC is more prevalent.

I have one six-piece "Whitworth" socket set, a few old Triumph toolbox open end wrenches, and a few BA wrenches and the rest is SAE (before everyone attacks, SAE/Imperial/USCS or whatever you call modern not-metric!).
 
Joined
Aug 8, 2005
Messages
2,252
Country flag

Beaneater,​

as Greg Marsh stated above,
You can try this company which is near your stomping grounds: https://britishfasteners.com/
7696 Route 31
Lyons NY 14489
USA
315-946-9400
If you get into the engine and gearbox then you need whitworth. SAE and AE are the same.
Cheers,
Tom
 
Joined
Jan 18, 2020
Messages
323
Country flag
I use Koken brand sockets and Laser brand spanners which are decent.
Plus the Gedore 1/4W spanner I bought for my first Norton 55 years ago.
Norton mostly used British Cycle threads (CEI, BSC) until the Commando, which gradually changed to UN threads..
The sizes of the hex was standardized by Mr. Whitworth in the eighteenth hundreds. Reasons for his choice of hex dimensions is unclear. Later In the US, Society of American Engineers (SAE) made the standard which after 1948 was renamed Unified National (UN). Mostly used is the coarse (UNC) and the fine threads (UNF). The hex head is measured across flats (AF).
In most of the world, metric threads are preferred, where hex sizes also is measured AF.
For some reason the British switched to standardize UN in the 1960ies. And fairly recent they've gone metric (inch by inch).
Then of course you on some rare places (mainly electrical) you can find BA screws, where hex heads are different from anything else. But some of those are quite close in size to metric. I've never bothered to buy BA tools.
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
16,886
Country flag
The vast majority of the nuts and bolts on a Commando are SAE.

They're 'Unified' as Mike40M said, so items manufactured in the UK would have been made to Unified Thread Standard (which became BS 1580).

SAE was fine thread, now UNF.

"The USS standard is no longer supported. It, together with the SAE fastener standard, was incorporated into the Unified Thread Standard. However, the term, USS, continues to be used occasionally today to describe inch based threaded fasteners with a coarse thread pitch and inch based washers that are a little bit larger than the corresponding SAE washer. The Unified Thread Standard uses the term UNC (Unified Coarse) to describe a fastener that previously would have been designated USS and the Unified Thread Standard uses the term UNF (Unified Fine) to describe a fastener that would have previously been designated SAE."



Norton mostly used British Cycle threads (CEI, BSC) until the Commando, which gradually changed to UN threads..
Although a few threads were subsequently changed during production certainly not all were, the majority were Unified thread from the beginning of Commando production and those that were British Standard mostly remained to the end of Commando production.
For some reason the British switched to standardize UN in the 1960ies.

The British motorcycle industry was somewhat late doing so.
And fairly recent they've gone metric (inch by inch).

I wouldn't say fairly recently as it mainly occurred during the late 1970s - early 80s.


No - same thing - just what we call them here in Oz.

...Also in the UK and other Commonwealth countries where the Imperial system had been adopted in 1826.

The USA, however, uses the customary unit system and although the inch is the same, certain measures as we know (fluid ounces, gallons etc.) are not.
 
Last edited:

marshg246

VIP MEMBER
Joined
Jul 12, 2015
Messages
1,386
Country flag
Since this is a thread about wrenches the thread types are not overly important. UNF/UNC/SAE/USS and others all use what we in the US call SAE wrenches, sockets, and Allen keys (3/8", 7/16", 1/2", 9/16", etc. wrench sizes). As L.A.B. implied, the British wrench sizes are Whitworth (even though the threads may not be).

Commandos use a lot of UNF threads. The gearbox uses British threads (I think some BSF and some CEI/BSC). The engine uses a combination of threads. Most of the cycle parts are UNF. It seems to me the 7/16" and 1/2" are the most common.

An interesting thing is that the British motorcycle companies started the switch to unified threads just as the Japanese were starting to sell big in the US. I don't know what prompted the change but the motorcycle world was heading to metric so in hindsight metric would have made more sense.
 

Bodger

VIP MEMBER
Joined
May 9, 2017
Messages
304
Country flag
Although UNF began as an attempt at standardization among the US, UK and "Commonwealth" countries during WW2, it was not formally adopted until after the war It is ironic that, globally, it has largely been displaced by metric standards used by the defeated Axis powers. Among the many screwy (bad pun intended) decisions made by the UK motorcycle industry was the decision to start switching to UNF in the 1960's, just as metric standards were achieving dominance in most of the world. Since the Commando went into production at the beginning of what was supposed to be a changeover to UNF, it is a mix of UNF and the various preexisting UK thread forms. As a related bit of trivia I have always wondered whether, when Packard obtained the contract to manufacture the Rolls Royce Merlin engine used in the P51, they switched to US thread forms. I know they spent several months redrawing the plans before they started manufacture.
 

grandpaul

VIP MEMBER
Joined
Jan 15, 2008
Messages
12,024
Country flag
Here is my set of Whitworth wrenches-
wrenches.jpg
Here is my Metric wrench set-
wrenches.jpg

...my SAE wrench set-
wrenches.jpg

...and my Mexican wrench set-
wrenches.jpg
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
16,886
Country flag
As a related bit of trivia I have always wondered whether, when Packard obtained the contract to manufacture the Rolls Royce Merlin engine used in the P51, they switched to US thread forms.

We seem to be drifting off-topic, however:
"Packard Built Merlins

An often asked question is; "did Packard replicate the British thread system when they built Rolls-Royce Merlins under license during World War II?" The answer is yes; all threads that were used on the Merlin were accurately replicated by Packard. This would include BSW (British Standard Whitworth), BSF (British Standard Fine), BSP (British Standard Pipe) and BA (British Association). Having said that, however, Packard Merlins used U.S. built Bendix injection carburetors; PD-16 for single stage engines and PD-18 for two stage engines, both of which used U.S. Unified threads. British built Merlins employed S.U. carburetors using Whitworth threads. The job facing Packard when they undertook manufacture of the Merlin was daunting to say the least. It’s bad enough having to build a complex product like the Merlin but exacerbating the situation was the fact no tool maker in the U.S. made Whitworth taps or dies. Therefore, Packard were forced into making their own. Although this created a significant hurdle to overcome, the effort was well worth it, Packard and Rolls-Royce components were interchangeable."
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
16,886
Country flag
Since this is a thread about wrenches the thread types are not overly important.

As the OP appears to have only recently discovered the reason why his metric tools don't fit his Commando's fasteners after several years of ownership then I'd think some background information explaining the differences between fastener types could still be useful.
 

MichaelB

"Sons of Arthritus"
VIP MEMBER
Joined
Jan 14, 2004
Messages
1,610
Country flag
Although UNF began as an attempt at standardization among the US, UK and "Commonwealth" countries during WW2, it was not formally adopted until after the war It is ironic that, globally, it has largely been displaced by metric standards used by the defeated Axis powers. Among the many screwy (bad pun intended) decisions made by the UK motorcycle industry was the decision to start switching to UNF in the 1960's, just as metric standards were achieving dominance in most of the world. Since the Commando went into production at the beginning of what was supposed to be a changeover to UNF, it is a mix of UNF and the various preexisting UK thread forms. As a related bit of trivia I have always wondered whether, when Packard obtained the contract to manufacture the Rolls Royce Merlin engine used in the P51, they switched to US thread forms. I know they spent several months redrawing the plans before they started manufacture.
The Hubris of the Brits and the Americans didn't allow them to see they were about to get run over....
 
Joined
Jan 18, 2020
Messages
323
Country flag
It is ironic that, globally, it has largely been displaced by metric standards used by the defeated Axis powers.
The metric system is a French invention, which is so logical that it spread to Germany, Italy and Japan and a lot of other countries.
Though the UN standard has some advantages over metric. The standardization of both a coarse and a fine thread is much better than the Metric where there is a lot of fine threads. France used even hex sizes and the Germans used odd hex sizes. Internationally the German DIN system was adopted. Then some years ago they reversed to even hex sizes. So an M8 can have either 12 or 13mm spanner size. A M10 can be 16 or 17. A M12 can be 18 or 19. So you need a lot of spanners and sockets. In the UN system you need fewer spanners and you can easily see what spanner you need for a nut.
 
Joined
Feb 18, 2018
Messages
522
Country flag
The metric system is a French invention, which is so logical that it spread to Germany, Italy and Japan and a lot of other countries.
Though the UN standard has some advantages over metric. The standardization of both a coarse and a fine thread is much better than the Metric where there is a lot of fine threads. France used even hex sizes and the Germans used odd hex sizes. Internationally the German DIN system was adopted. Then some years ago they reversed to even hex sizes. So an M8 can have either 12 or 13mm spanner size. A M10 can be 16 or 17. A M12 can be 18 or 19. So you need a lot of spanners and sockets. In the UN system you need fewer spanners and you can easily see what spanner you need for a nut.
Interesting- that explains 10 or 11 mm spanners for 6 mm bolts!
 

cliffa

VIP MEMBER
Joined
May 26, 2013
Messages
2,251
Country flag
Hello all,

I have many wrenches in my garage but none of them seem to fit on any darn bolt on my Commando. My neighbor told me that the British have a differently sized set of tools than we do here in the USA. Is Whitworth the right "style"? As opposed to SI/Metric/JIS.

If so then can anyone here recommend a place where I can purchase a set of Whitworth tools at a reasonable price? I see some Norton Specific tool rolls but the prices make me cringe. $90 for 8 wrenches hurts. :eek:

Thanks for your help!
You may want to consider a set of Metrinch spanners and sockets. They fit metric and imperial because they drive on the flanks of the hexagon not on the points so can be a looser fit. I know they used to be made in the U.S. but now not sure. Regardless they have a very good reputation and if I were starting out that’s what I’d get.

here’s and example combo set..


Cheers,

cliffa.
 
Last edited:
Top